What technology did the government use to gather evidence against dlk?

Police and other government entities in the United States have used different technological tools to gather evidence in the cases they are investigating. A well-known case is called DLK by the initials of an Oregon person involved in the investigation. Federal police suspected that DLK had marijuana crops in the house.

A thermal imager was used to scan the DLK residence from outside. The results showed a heat similar to that generated by the special lights that are used to grow marijuana indoors. With these results and other information that had been raised, a judge issued a search warrant for the house. 100 marijuana plants were found. Agents arrested DLK.

The use of these tools and technologies have opened debates and Constitutional issues as some people claim that they violate Fourth Amendment rights.