When an officer is justified in believing that the individual whose suspicious behavior he is investigating at close range is armed and presently dangerous to the officer or to others, he may conduct a limited protective search for concealed weapons. Adams v. Williams, 407 U.S. 143, 146 (1972) (citing Terry v. Ohio, 392 U.S. 1 (1968)).

This belief may be based on information provided to the officer by an informant; it is not required that the officer observe the suspicious activity himself. Adams, 407 U.S. at 147.

A police officer's pointing a gun at a suspect does not necessarily convert an investigatory stop into an arrest. In re David S., 367 Md. 523, 535 (2002).

“An investigatory stop will not be transformed into an arrest when the officers take reasonable measures to neutralize the risk of physical harm and to determine whether the person in question is armed.” Id.

citing Cotton v. State, 386 Md. 249, 265 (2005), noted that “the last decade has witnessed a multifaceted expansion of Terry, including the trend granting officers greater latitude in using force in order to neutralize potentially dangerous suspects during an investigatory detention. For better or worse, the trend has led to the permitting of the use of handcuffs, for the placing of suspects in police cruisers, the drawing of weapons and other measures of force more traditionally associated with arrest than with investigatory detention.” Cross, 165 Md. App. at 179.

If, while conducting a legitimate Terry search of the interior of the automobile, the officer should discover contraband, he clearly cannot be required to ignore the contraband, and the Fourth Amendment does not require its suppression in such circumstances. Michigan v. Long at 1050.

It is well established that “without effecting an arrest, a police officer with reasonable suspicion, supported by articulable facts that criminal activity ‘may be afoot,’ may stop and detain a person, briefly, for investigative purposes.” Longshore v. State, 399 Md. 486, 506 (2007).

Police officers, in certain situations, such as those evidencing the need for officer safety, have authority to use force, including use of handcuffs and drawn weapons, to enforce an investigatory stop. Id at 517 (holding that where there was no suspicion that the defendant was armed or a flight risk, use of these techniques requires probable cause).

While "reasonable suspicion" is a less demanding standard than probable cause and requires a showing considerably less than preponderance of the evidence, the Fourth Amendment requires at least a minimal level of objective justification for making the stop. Illinois v. Wardlow, 528 U.S. 119, 123 (2000). The officer must be able to articulate more than an "inchoate and unparticularized suspicion or 'hunch'" of criminal activity. Id at 123-4.

“Reasonable suspicion is a less demanding standard than probable cause not only in the sense that reasonable suspicion can be established with information that is different in quantity or content than that required to establish probable cause, but also in the sense that reasonable suspicion can arise from information that is less reliable than that required to show probable cause.” Trott v. State, 138 Md. App. 89, 116 (2001).

Whren v. United States, 517 U.S. 806, 814, 116 S.Ct. 1769 (1996) The constitutional reasonableness of a traffic stop does not depend on the actual motivations of the individual officers for the stopping of the vehicle. “Subjective intentions play no role in ordinary, probable-cause Fourth Amendment analysis”, “The Fourth Amendment’s concern with ‘reasonableness’ allows certain actions to be taken in certain circumstances, whatever the subjective intent.”

In re David S., 367 Md. 523, 529 (2002) (hard take down & cuff can still be terry stop)

Trott v. State, 138 Md. App. 89, 119 (2001) (handcuff of known, nervous flight risk can still be terry stop)

Illinois v. Wardlow, 528 U.S. 119, 120 S.Ct. 673 (2000) – defendant’s unprovoked sudden flight in high crime area from presence of officer provided reasonable suspicion for Terry seizure.

NOT reasonable articulable suspicion:

Without more, anonymous tip that defendant had a gun. Florida v. J.L., 529 U.S. 266 (2000)

Reasonable suspicion is a less demanding standard than probable cause not only in the sense that reasonable suspicion can be established with information that is different in quantity or content than that required to establish probable cause, but also in the sense that reasonable suspicion can arise from information that is less reliable than that required to show probable cause.
Carter v. State, 143 Md. App. 670, 680 (Md. Ct. Spec. App. 2002)

nervous, evasive behavior is a pertinent factor in determining reasonable suspicion. Headlong flight--wherever it occurs--is the consummate act of evasion: it is not necessarily indicative of wrongdoing, but it is certainly suggestive of such
Carter v. State, 143 Md. App. 670, 681 (Md. Ct. Spec. App. 2002)