Shopping centers, stadiums and universitiesmay soon have a new tool to help fight crime.A California company called Knightscopesays its robots can predict and prevent crime.Knightscope says the goal is to reduce crime by halfin areas the robots guard.William Santana Li is the chief executive officer of Knightscope.He says these robot security guards will change the world."Our planet has seven billion people on it. It's going to quickly get to nine billion people.The law enforcement apparatus and security apparatus that we have globally is just not going to scale."Mr. Li says his company's Autonomous Data Machinescan become the eyes and ears of law enforcement."You want it to be machines plus humans.Let the machines do the monotonous computational heavy and sometimes dangerous workand let the humans do the strategic decision-making work so it's always working in tandem."The machines are one and a half meters tall and weigh 136 kilograms.They do not carry weapons but have day and night time video cameras able to turn 360 degrees.Mr. Li says they can also sense chemical and biological weapons.Eugene Volokh is a law professor at the University of California.He says the machines have to be used in the right way.He says some people may become concerned about their privacy,especially in connection with the video recordings.Some people may worry that such recordings will appear on the Internet.Mr. Volokh says it will be interesting to see how state laws deal with this kind of surveillance video.William Santana Li says there is a long waiting list for the robots in the U.S.At least 25 other countries are also interested in these robotic security guards.Words in this Storystadium - n. a very large usually roofless buildingthat has a large open area surrounded by many rows of seatsand that is used for sports events, concerts, etc.apparatus - n. the organization or system used for doing or operating somethingscale - n. the size or level of something especially in comparison to something elsestrategic - adj. useful or important in achieving a plan or strategyin tandem - n. two people, groups or things working or happening together or at the same timesurveillance - n. the act of carefully watching someone or somethingespecially in order to prevent or detect a crimeDoes the idea of robotic guards make you feel uneasy?Do you think it is a good way to reduce crime?Let us know. Post your thoughts in the comments section?