NASHVILLE, Tenn. -- There are critical questions about police tactics that led to the capture of the suspected "Wooded Rapist."

Video: Use Of Tracking Device Questioned In Rape Case

Brentwood investigators said they secretly planted a GPS tracking device on Robert Jason Burdick's car, which helped to arrest him.

It has become the subject of legality issues and whether or not it will become a factor as the case developments.

Brentwood Police planted a GPS-type tracking device on Burdick's Jeep that they used to help arrest him.

Police did not have a court order or search warrant to use the device. Nashville criminal defense attorney David Raybin believes the absence of a warrant ultimately jeopardizes the case.

"I believe that doing so without a search warrant or court order is unlawful. You can't put tracking devices on people's cars without violating the fourth amendment," said Raybin told Channel 4 News by phone on Friday.

Brentwood Police Chief Ricky Watson fired back at Raybin's analysis by saying, "What we did was legal. Everything we did was above board and legal."

Critics believe every piece of evidence will be tossed out from the point the tracking device was placed on Burdick's Jeep until his arrest by Brentwood police on May 1.

Police followed Burdick to a LaVergne restaurant and confiscated silverware for DNA purposes. Raybin said it's possible the restaurant evidence will be thrown out.

"I anticipate his lawyers will probably file a motion to suppress and through out any evidence that was secured as a result of this tracking. If they tracked him to the restaurant, for example, where they ended up getting the DNA evidence, that could possibly through that out," said Raybin.

Here's what Tennessee law says regarding the issue:

"It's not a violation for law enforcement to place tracking devices on motor vehicles in the course of criminal investigation. But it has to be done in accordance with state and federal law."

Channel 4 News found in numerous instances where law enforcement agencies are using tracking devices in cases.

These cases are being challenged and it is being found that different courts are making different rulings regarding the legality of the tracking devices.

Burdick is accused of 13 rapes in Davidson, Williamson and Wilson counties.

Investigators believe the first rape took place in 1994, and the last assault occurred just three months ago.