BOISE — A transgender woman who police say planted what appeared to be four pipe bombs then set fire to her trailer home and car became the first person to be charged under a new state law involving hoax explosive devices. Catherine Carlson, 53, was charged in 3rd District Court with felony arson and planting a hoax destructive device. The latter charge was created under a law passed by the 2010 Legislature targeting those who try to incite public panic. “The new law fits perfectly with this case,” Payette Police Chief Mark Clark said Tuesday. Carlson could face a total of 15 years in prison if convicted of both charges. She was arrested Sunday in Payette. Police said an investigation later revealed the pipes contained no explosives. About 50 homes were evacuated after firefighters responded to the trailer fire and found the pipes near a propane tank. Authorities have said Carlson indicated she planted the devices, set the fires then shed her clothing in a bid to draw attention to her plight as a transgender person. In 2007, Carlson clashed with authorities over a traffic citation after they included her given name, Daniel Carlson, on some documents. The name Daniel Carlson is listed as an “aka,” or “also known as,” on citation records. Carlson fears court documents that make public her decision to legally change her name in the 1970s then alter her sex with an operation in 1980 could put her life in danger. Clark said court documents in the current case only include Carlson’s current, legal name. Efforts to contact Carlson in Payette County jail were unsuccessful. At a hearing Monday, Carlson asked for permission from the judge to represent herself in the case. Idaho lawmakers wanted to give law enforcement officials more authority to go after hoax explosive reports such as one in 2009 when suspicious devices were placed at a Boise shopping center. The false alarm forced 2,000 people to evacuate and shuttered stores for hours. Rep. Marv Hagedorn, R-Meridian, sponsored the new law that went into effect July 1 and carries a five-year prison term. Carlson’s latest arrest came after her car was impounded on July 7 by police in Ontario, Ore., a town just across the Idaho border from Payette. Her mental health was evaluated, and she was released later that day, authorities said. “Obviously, there’s some issues here” with mental health concerns, Clark said. “But there are also some very serious crimes.” A call to the Ontario Police Department wasn’t immediately returned.